There comes a point in every system's life where the big purchases are done and the remaining gains hide in the margins. This is accessory territory, and it is where scepticism reaches its healthy peak. Cable risers? Caps for unused sockets? A box that pretends to be the earth? We approached this category with our eyebrows fully raised, and we report back with them only partially lowered, in the best possible way.
Furutech NCF Booster: the elevator that works
The NCF Booster family, including the Booster-Signal and Booster-Signal-L, does two jobs at once. As cable supports, they lift runs off the floor and take the mechanical strain off connectors, which alone justifies them. But the NCF material they are built from, a nano crystalline compound with piezoelectric properties, also damps vibration and static at the contact point. With Boosters under the speaker cables and a Signal-L cradling the power cord at the amplifier, the change on Hans Zimmer's "Time" was a blacker background behind the build-up and a cleaner attack on the final crescendo. Modest, repeatable, and the sort of thing you miss immediately when removed.
Clear Line and the Flux filters
The Clear Line LAN, USB and XLR caps are the definition of a small experiment: they plug into unused sockets and passively absorb noise at the entry point. The LAN and USB versions, fitted to a streamer and DAC respectively, brought a slight but consistent easing of digital glare on streamed tracks. The inline Flux-50 and Flux-C15 NCF filters, along with the Flow-C15, go further, filtering the mains at the component end of the power cord. The Flux-50 on our DAC's IEC inlet produced the single clearest accessory effect of the test: quieter background, less hash, and no loss of dynamics.
Kojo Crystal E: the earth that is not one
The strangest product we stock is also one of the most effective. The KOJO Crystal E is a virtual earth box: a container of conductive material that gives your equipment's ground wires somewhere to dump noise without a connection to the physical earth. Its bigger sibling, the Crystal E-G, multiplies the effective ground area dramatically. Connected to the ground terminal of a phono stage, the Crystal E dropped the residual hum of our reference turntable rig from faint to absent, and brought a new stability to the stereo image that had us rechecking the speaker positioning. In apartments and older Australian homes where real earthing is a fantasy, these boxes are close to essential.
Verdict
None of these products will transform a mediocre system, and we would never suggest buying them before the fundamentals are right. But once they are, the NCF Boosters and a Crystal E are among the most cost effective refinements we sell. Start with the Flux-50 or a pair of Boosters, listen for a week, and try to give them back. Most people do not.